Microspectrofluorometry of Oriented Myofibrils

荧光显微镜耦合到一个光子计数荧光分光光度计将用于获得荧光光谱，荧光检测二色性和荧光偏振数据标记的原肌球蛋白，肌动蛋白和肌钙蛋白纳入定向肌肉肌原纤维和纤维。先前的研究表明，当肌球蛋白头与不含调节蛋白的鬼纤维结合时，以及当钙离子与缺乏肌球蛋白的细丝上的调节蛋白结合时，肌动蛋白亚基会轻微地重新取向。没有研究似乎已经报道了可能的重新定位肌动蛋白亚基与肌球蛋白头结合到肌动蛋白含有调节蛋白。该项目将提供与体内肌肉系统调节相关的亚基重定向的新信息，并将有助于阐明肌肉收缩调节的机制。

A fluorescence microscope coupled to a photon counting spectrofluorometer will be used to obtain fluorescence spectra, fluorescence-detected dichroism and fluorescence polarization data on labeled tropomyosin, actin and troponin incorporated into oriented muscle myofibrils and fibers. Prior work on fibers has indicated that actin subunits slightly reorient when myosin heads bind to ghost fibers not containing the regulatory proteins and when calcium binds to the regulatory proteins on the thin filament in the absence of myosin. No studies appear to have been reported of possible reorientation of actin subunits associated with myosin head binding to actin containing the regulatory proteins. This project will provide new information about subunit reorientation assoicated with regulation in systems that are close to in vivo muscle and will help to clarify the mechanism of the regulation of muscle contraction.***//